Electric contact makers and connectors fitted with such devices

ABSTRACT

Electric contact maker made of a metal strip and designed to be inserted in an insulating frame comprising guiding grooves for the opposite edges of the strip. The part of the strip having said edges includes a narrower zone from which a longitudinal tongue has been cut out and also a counter-tongue the free tip of which comes into contact with the tongue near their free ends.

United States Patent 1191 Bonhomme [4 1 Apr. 30, 1974 1 ELECTRIC CONTACTMAKERS AND 3,052,867 9/1962 Rogoff 339/217 5 CONNECTORS FITTED WITH SUCHI 3,693,134 9/1972 Trevisiol 339/59 M DEVICES FOREIGN PATENTS ORAPPLICATIONS [75] inventor: Francois Robert Bonhomme, 1,330,195 5/1963France 339/217 5 Saint-Cloud, France [73] Assignee: ConnectronicsCorporation, New Primary Examiner 30bby y York, NY AssistantExaminer-Robert A. Hafer Attorney, Agent, or FirmWaters, Roditi,Schwartz & [22] Filed: Apr. 6, 1972 Nissen [21] Appl. No.: 241,528

- 57 ABSTRACT [52] 339/217 339/17 339/176 Electric contact maker made ofa metal strip and de- 339/258 R signed to be inserted in an insulatingframe comprising [51 1 Int. Cl "01! 9/08 g g grooves for the pp i edgesf the Strip. [58] Field of Search 339/217 S, 252, 256, 258,

The part of the strip having said edges includes a 339/259, 176 MP, 17 Lnarrower zone from which a longitudinal tongue has [561 CM3112:2212;121:2:1121112'11 92 I? 2:31,? UNITED STATES PATENTS free ehds'6 g e n r 3,697,926 /1972 Krafthefer 339/17 L 3,626,361 12/1971 Bonhomme339/217 S 9 Claims, 3 Drawing Figures 1 7 Q E\1\1\ ()6 J21 1 3a 65 f I lQ a] h 5;,

ELECTRIC CONTACT MAKERS AND CONNECTORS FITTED WITH SUCH DEVICES frame,the segment being cut out in such a way as to form at least one flexiblelongitudinal tongue designed to rest against at least one longitudinalsupport surface provided in the frame; the abovesaid part of the strip,the edges of which are designed to be inserted in the above-mentionedguiding grooves adjoining a connecting portion of the strip on one side,and on the other a flexible loop made to ensure electric contact with aconducting surface of the contacting element.

It is an object of the invention to make the such electric contactmakers fulfil the various exigencies of practice better than hitherto,and, in particular to enable economical manufacture and high safety inuse.

According to the invention, an electric contact I maker of the typedescribed is characterised by the fact that the above part of the strip,having edges made to be inserted in the guiding grooves of theinsulating support includes a narrower zone from which a longitudinaltongue has been cutout; this zone is extended by means of the flexibleloop, which loop has a free end and is cut out so as to have on the onehand two lateral strips meeting at the free end of the loop, and on theother hand a counter-tongue having a free tip at the opposite end to thefree end of the loop and which approaches said tongue so as to contactthe latter, the counter-tongue pushing up against the frame therebycontributing to the locking of the contacting element in the support.

Preferably, the narrower zone, from which the tongue has been cut out,is displaced in relation to the edges designed to be guided by thegrooves of the insulating frame, on the side opposite the free end ofthe flexible loop.

Advantageously the abovesaid part of the segment, in the area where theedges are provided, is thicker than the area from which the tongue andthe flexible loop have been cut out- Preferably this thickness of thearea in which said edges are provided is slightly greater than theuseful height of the grooves, so that the contacting element must beforced into these grooves.

The invention also relates to electrical connectors characterised by thecombination of an insulating frame and at least one electric contactmaker such as defined above.

Apart from the features described above, the invention consists ofcertain other features which are used preferably at the same time andwhich will be more explicitly considered below with regard to apreferred embodiment of the invention, which will now be described inmore detail, with referenceto the attached drawings, but which is in noway limiting.

FIG. 1 of these drawings shows, in perspective, with according to theinvention.

FIG. 2 shows in cross-section an insulating support frame fitted with anelectric contact maker similar to the one in FIG. 1.

Lastly, FIG. 3 shows in perspective, with parts detached, a housing ofthe insulating support frame for the electric contact maker.

Referring to FIG. 1 it is seen that the electric contact maker-1 is madeup of a metal conducting strip or segment with a part 3 in which an area3a includes edges B designed to be guided by the grooves 35 (see FIGS. 2and 3), cut into an insulating frame 28. The metal segment 3 adjoins thesocket on one side, extending the area 3a, and on the other a flexibleloop 5 ensuring electric contact with a conducting surface, inparticular a printed circuit card.

Part 3 of the segment includes a Zone 3b narrower than the area 3a. Alongitudinal tongue 6 has been cut out of zone 3b. This tongue isdesigned to abut against one or several longitudinal supporting surfacesprovided in the insulating frame 28, and which will be discussed below.Zbne 3b extends the area 3a while the flexible loop 5 extends zone 3b.

The loop 5 is open and has a longitudinal section curved back in theshape of a hook, as is obvious from the drawings. The free end 5a of theloop 5 is lengthwise substantially at the level of the nearest part ofthe area 3a to zone 3b. The mean plane of the end 5a is substantiallyparallel to the mean plane of the area 3a.

The above loop 5 has itself been cut out in such a way as to form on theone hand two lateral strips l5, 16, extending the strips of the zone 3bsituated on either side of the tongue 6, and on the other hand acountertongue 60, whose free tip 61, which is at the opposite end of theextremity 5a of the loop, is brought back close so as to contact thetongue 6. The tongue 6 and the counter-tongue 60 have a generalrectangular shape, the mean plane of the'tongue 6 being substantiallyparallel to that of area 3a, while the mean plane of the counter-tongue60 is sloping relative to that of the area 3a.

Advantageously, the free end of the tongue 6 and the free end 61 of thecounter-tongue 60 are concave, in the same direction as the loop 5. Thelateral strips 15 and 16 form two simple loops situated on either sideof the counter-tongue 60 and meeting at the free end 5a of the loop 5.The lateral strips 15 and 16 are separated by a continuous slot F, theextended length of when extended is substantially equal to the sum ofthe lengths of tongue 6 and counter-tongue 60. The latter, near its end61, traverses the slot F.

The tip 61 of the counter-tongue 60, as shown in FIG. 2, is designed topush the tongue 6 up against the insulating frame 28 and to facilitatethe locking of the contact maker 1 into the frame.

The other end 61a of the counter-tongue 60 joins the free end 5a of theloop 5, the counter-tongue 60 (like the tongue 6) being cut out on threesides only. The metal has been bent at the level of the end 61a so thatthe tip 61 touches tongue 6.

Preferably, the area 3a is of greater thickness e than the zone 3b andthe loop 5, the thickness e of the area 3a being itself slightly greaterthan the useful height 41 (FIG. 2) of the grooves 35 of the frame 28. Inthis way the area 3a of the contact maker must be forced into thegrooves 35 and the transverse support in relation to the grooves 35 ofthe contact maker is effected automatically. The area 3a may be bent inorder to afford give it, while relaxed, an overall thickness greaterthan the useful height of the grooves. In the case of the embodiment ofFIG. 1, the area 30 is substantially flat.

It is also preferable that the zone 3b be displaced in relation to thearea 30 and the edges B by a distance f on the opposite side to the end50 of the flexible loop so that a shoulder 3c is formed at the junctionbetween the area 3a and the zone 3b.

To ensure the lengthwise locking of the contact maker in the frame 28,two protrusions 62, 63, adapted to rest against the longitudinalsupporting surfaces 64, 65 (FIGS. 2 and 3), are provided in the frame28, on each side of the tongue 6.

The protrusions 62, 63 are made up of two flaps from the tongue 6,formed on one side by a cut made transversally, approximately halfwayacross the width of this tongue.

These protrusions 62, 63 are separated from one another lengthwise andare in'between the above mentioned cuts. The protrusions are obtained byfolding back and lifting up an area approximately triangular, on theside of the tongue 6 opposite the loop 5.

The longitudinal supporting surfaces 64, 65 (FIGS. 2 and 3) are made upof the longitudinal ends of the bosses 66, 67 provided on part 68 of thesurface of'the frame turned towards the tongue 6.

Each of the bosses 66, 67 extends transversally, as shown by the doublearrow T in FIG. 3, over a fraction of the width 1 of this part 68, oneach side of the latter. The sum of the widths of the bosses 66, 67 issmaller or equal to 1, the width of each boss being preferably equal tothe half of l.

The bosses 66, 67 extend lengthwise, starting from each end of the frame28 and the lengths of the bosses are such that the internal longitudinalends 64, 65 of these bosses are separated from each other by alongitudinal distance g (FIG. 2) so that there exists in the casing 31of the contact maker 1, provided in the frame 28, a space R free of anyboss, into which the protrusions 62, 63 of the tongue 6 fit.

The distance g (FIG. 2) between the longitudinal supporting surfaces 64,65 is equal or slightly less than the distance separating thetransversal sides of the protrusions 62, 63, designed to come intoabutment with the abovesaid longitudinal supporting surfaces, so thatthe stopping of the contact maker 1 in the frame 28 is ensured withoutsubstantial longitudinal play.

The frame 28, into which contact makers such as l are designed to befitted, comprises series of housings 31 of substantially rectangulartransversal section, separated by partitions 32 and open at their twoends. These housings and these partitions form two series symmetrical inrelation to the plane of line 29, corresponding to the mean plane of aprinted circuit card designed to be introduced into the space E betweenthese series of partitions. The check or stop 33 provided on the frame28 is designed to limit the admission of the printed circuit card. Thischeck 33 includes clearances 33a, of perpendicular transversal section,turned towards the space E and adapted to take the free end a of theloop 5 of a contact maker.

Advantageously the free end 5a of the flexible loop 5 is situated, whenrelaxed, at a distance H (FIG. 1) from the middle axis of the area 3a,greater than the distance (FIG. '2) separating the middle axis of agroove 35 from the surface of the gap 33a against which the end 5a willabut. Under these conditions, in order to cause the device to occupy theposition shown in FIG. 2, a compressing force must be exerted on theloop 5, which, because of its elasticity, remains in abutment againstthe surface 33a.

To fix a contact maker 1 in a housing 31 of the frame 28, this contactmaker may be introduced, correctly oriented, through one of the two openends of the housing 31, that is to say as depicted in FIG. 2; one canoperate from the right or left of the frame 28.

When the introducing is effected from the right of the frame, thecontact maker 1 is oriented in such a way that the loop and the tongue 6are introduced first into the housing 31, the free end 5a being turnedtowards the mean plane of the frame 28. Care should be taken to insertthe edges of the area 3a in the grooves 35.

The free end 5a must must be lifted up to pass the check 33 and becauseof the elasticity of loop 5, the end 5a returns automatically into thegap 33a. The compression on loop 5 is self-effected.

When the protrusions 62, 63 come into line with the free space R, thetongue 6 moves away from loop 5 and said protrusions, by co-operationwith the longitudinal supporting surfaces 64, 65, and ensure thefastening of the contact maker 1 in the frame 28.

If the introducing had been effected from the left of FIG. 2, a wedgewould have been set up in the free space E, designed to press down onloop 5 and to enable correct placing of the end 5a in the gap 33a.

The removal of the contact maker 1 from the frame 28 can be effected,like the introduction, from either end of the housing 31, that is, fromthe front or the back of the connector, frame 28. To effect thisremoval, one must on the one hand disengage the protrusions 62, 63 fromthe space R, for example with the aid of a suitable tool, introducedbetween the tongue 6 and the frame 28, and on the other hand exert anextraction force on the contact maker 1 either towards the right or leftof FIG. 2. It must be noted that, when one wants to remove the contactmaker 1 towards the right of FIG. 2, a wedge must first be introducedinto the space E enabling the loop 5 to be sufficiently compressed sothat the free end 5a is freed transversally from the check 33 and doesnot hinder the removal of the contact maker 1 towards the right of FIG.2.

As can be seen in FIG. 2, the curved end of the counter-tongue issupported against the tongue 6, in the latter zone of which there arethe protrusions 62, 63. The counter-tongue 60 acts as a brace in beingurged against the free end 5a, and as a result, the check 33, to exert aholding force on the tongue 6, which holding force contributes to thesafety of the longitudinal locking of the contact maker 1 in frame 28.

According to a modification, the co-operation of tongue 6 and frame 28ensures the locking of contact maker 1 in frame 28 only in a directionwhich corresponds, for FIG. 2, to the direction going from right toleft. This locking will be ensured, for example, by the protrusion 62acting in conjunction with the supporting surface 64. Locking in theother direction that is for FIG. 2 from left to right, will not beensured either by a protrusion such as 63 acting in conjunction with asurface 65 but by the shoulder 30 acting in conjunction with a boss (notshown) provided on the frame 28. According to this modification thefixing of the contact maker 1, in the frame 28 is only possible in onedirection, from left to right for FIG. 2; it is the same for the removalof contact maker 1, from the frame 28 which is only possible in theopposite direction to the one just considered.

The frame 28, shown in FIG. 2, is adapted to receive two series ofcontact makers 1, symmetrical in relation to the plane of line 29.Because the free ends 5a of the contact makers are in abutment againstthe surfaces of the gaps 33a as a result of the compression of the loop5, the spacing between the zones of the two contact makers 1,symmetrical with respect to the plane of line 29, is fullypre-determined and equal to the thickness of the check 33 at the levelof the gaps 33a.

The quality of the electric contact obtained between the contact maker 1and a printed circuit card introduced into space E, is safe and may bereproduced exactly. Indeed, not only is contact obtained by means of twolateral strips 15, 16 constituting a sort of double contact segment, butthe counter-tongue 60 forms, as seen in FIG. 2, a sort of deformablepolygon with loop 5. The counter-tongue 60, which forms one of the sidesof this polygon, exerts on the end 5a a force transmitted to the lateralstrips 15, 16 which is added to that due to the compression of theflexible loop 5 and facilitates the contact of said loop with theprinted circuit card. Besides which, the counter-tongue, by means of itstip 61, contributes to the locking of the contact maker 1 into the frame28 while maintaining tongue 6 in cooperation with this frame.

The two lateral strips 15, 16 of loop 5 are extremely independant ofeach other, since the opening F which separates these strips is verylong and practically equal to the sum of the lengths of thecounter-tongue 60 and the tongue 6. This independence of the strips and16 facilitates good contact.

When the printed circuit card has been introduced into the space E ofFIG. 2, if the mean plane of this card is sloping in relation to themean plane of line 29, of the connector, the point of thrust of the tip61 of the counter-tongue 60, against tongue 6, will be displaced, whichensures constant contact between the printed circuit card and theflexible loop 5 over substantially the whole length of the portion ofthe latter which is parallel to the plane of the line 29 and turnedtowards the space E. I

The counter tongue 60 exerts its effect on the loop 5 as soon as theprinted circuit card has been introduced into the space E, for the pointof contact of the tip 61 against the tongue 6 is situated longitudinallyat the level of the part of loop 5 which first comes into contact withthe printed circuit card.

Another advantage of a connector constructed according to the inventionto be pointed out is that the length of the loop 6 when extended isshorter than when the latter is shaped like an ellipse, and that thenecessary tools to cut this loop into two simple loops I5 and 16 are ofsmaller dimensions and are less expensive. This lowering of the cost ofproduction results on the one hand, in a reduction of the cost of theequipment necessary for the production of the contactor and on the otherhand, in a reduction of the raw material necessary for its production.

It must also be emphasised that the frame 28 may be cast very easilymeans of the advantageous placing of the bosses 66, 67, the ends ofwhich constitute the longitudinal supporting surfaces of the contactmaker 1. In fact one has merely to introduce into the mould through asuitable end of the housing 31, rods which will prevent the materialfrom spreading during casting, on the one hand between the longitudinalend 65 of the boss 67 and the open end of the housing 31 out of whichcomes the boss 66, and on the other hand, between the end 64 of the boss66 and the open end of the housing 31 out of which comes the boss 67.The removal of these rods after casting is easily effected.

As a result of which, an electric contact maker is obtained, whosefixing in the insulating frame is safe and whose production iseconomical. The forces exerted by this device on a conducting surface,such as that of a printed circuit card, are able to be reproduced mainlybecause of the action of the counter-tongue.

What is claimed is: I

1. An electric contact maker for forming a connector when inserted in aninsulating support frame adapted to receive a contacting element, saidcontact maker comprising a metal strip including a first portion having.edges adapted to be inserted in guiding grooves provided in theinsulating frame, and a second portion, narrower than the first, andextending in continuation thereof, said second portion including aflexible loop to ensure electrical contact with a conducting surface ofthe contacting element, and a connecting portion joining the loop to thefirst portion, said loop having a terminal free end remote from theconnection thereof to said connecting portion, said loop being providedwith a cut-out to form two lateral strips joined together at said freeend of the loop, a flexible longitudinal tongue adapted to abut at leastone longitudinal supporting surface provided on the frame, and acounter-tongue having a free end in contact with the first said tongueto press the same against the frame, thereby contributing to the lockingof the contact maker in the frame, said free end of said loop lying in aplane extending substantially parallel to said first portion to ensureconstant contact over substantially the entire length of said free endwith the contacting element.

2. Electric contact maker according to claim 1, wherein said secondportion is displaced in relation to the edges of said first portion.

3. An electric contact maker according to claim 1 wherein said firstportion is thicker than said second portion.

4. Electric contact maker according to claim 3, wherein the thickness ofsaid first portion is greater than the useful height of the insulatingframe so that the contact maker must be inserted by force into saidgrooves.

5. Electric contact maker according to claim 12, wherein thelongitudinal tongue comprises, on either side, a protrusion adapted torest against an adjoining longitudinal supporting surface provided inthe insulating frame.

6. Electric contact maker according to claim 5, wherein each protrusionis shaped out'of part of the tongue, bounded on one side by a cut madetransversally, approximately halfway across the width of the tongue,said part being shaped so as to form said protrusion on the oppositeside of the tongue to the side on which the flexible loop is situated.

7. Electric contact maker according to claim 5, wherein thecounter-tongue presses against the tongue close to said protrusions.

8. Insulating frame for the contact maker according to claim 5,comprising a housing open at both ends wherein the longitudinallysupporting surfaces are formed by the ends of bosses provided on part ofthe housing surface which is designed to turn towards the tongue, eachboss extending transversally, over a fraction of the width of said partof the housing surface, on either side of the latter, the sum of thewidths of the bosses being not greater than that of said part of thehousing surface, said bosses extending lengthwise from each end of theframe over a fraction of the length of the latter, the length of saidbosses being such that their inner ends are separated from each other soas to leave a space in the housing free of any boss in which said stopsurface of the frame, in a fixed position.

1. An electric contact maker for forming a connector when inserted in aninsulating support frame adapted to receive a contacting element, saidcontact maker comprising a metal strip including a first portion havingedges adapted to be inserted in guiding grooves provided in theinsulating frame, and a second portion, narrower than the first, andextending in continuation thereof, said second portion including aflexible loop to ensure electrical contact with a conducting surface ofthe contacting element, and a connecting portion joining the loop to thefirst portion, said loop having a terminal free end remote from theconnection thereof to said connecting portion, said loop being providedwith a cut-out to form two lateral strips joined together at said freeend of the loop, a flexible longitudinal tongue adapted to abut at leastone longitudinal supporting surface provided on the frame, and acounter-tongue having a free end in contact with the first said tongueto press the same against the frame, thereby contributing to the lockingof the contact maker in the frame, said free end of said loop lying in aplane extending substantially parallel to said first portion to ensureconstant contact over substantially the entire length of said free endwith the contacting element.
 2. Electric contact maker according toclaim 1, wherein said second portion is displaced in relation to theedges of said first portion.
 3. An electric contact maker according toclaim 1 wherein said first portion is thicker than said second portion.4. Electric contact maker according to claim 3, wherein the thickness ofsaid first portion is greater than the useful height of the insulatingframe so that the contact maker must be inserted by force into saidgrooves.
 5. Electric contact maker according to claim 12, wherein thelongitudinal tongue comprises, on either side, a protrusion adapted torest against an adjoining longitudinal supporting surface provided inthe insulating frame.
 6. Electric contact maker according to claim 5,wherein each protrusion is shaped out of part of the tongue, bounded onone side by a cut made transversally, approximately halfway across thewidth of the tongue, said part being shaped so as to form saidprotrusion on the opposite side of the tongue to the side on which theflexible loop is situated.
 7. Electric contact maker according to claim5, wherein the counter-tongue presses against the tongue close to saidprotrusions.
 8. Insulating frame for the contact maker according toclaim 5, comprising a housing open at both ends wherein thelongitudinally supporting surfaces are formed by the ends of bossesprovided on part of the housing surface which is designed to turntowards the tongue, each boss extending transversally, over a fractionof the width of said part of the housing surface, on either side of thelatter, the sum of the widths of the bosses being not greater than thatof said part of the housing surface, said bosses extending lengthwisefrom each end of the frame over a fraction of the length of the latter,the length of said bosses being such that their inner ends are separatedfrom each other so as to leave a space in the housing free of any bossin which said protrusions can be inserted.
 9. Electrical connectorcomprising in combination a contact maker according to claim 1 and aninsulating frame defining a housing so placed that the flexible loop ofthe contact maker has, when in relaxed condition, a transverse widthgreater than that of said housing, so that to fix the contact maker intothe above frame, a compressing force must be exerted on the loop whichforce maintains the loop in abutment against a stop surface of theframe, in a fixed position.